In the course of completing an oil and/or gas well, it is common practice to run a string of protective casing into the well bore and then to run the production tubing inside the casing. At the well site, the casing is perforated across one or more production zones to allow production fluids to enter the casing bore. During production of the formation fluid, formation sand is also swept into the flow path. The formation sand is relatively fine sand that erodes production components in the flow path.
In some completions, however, the well bore is uncased, and an open face is established across the oil or gas bearing zone. Such open bore hole (uncased) arrangements are utilized, for example, in water wells, test wells, highly deviated and horizontal well completions. One or more sand screens are installed in the flow path between the production tubing and the open, uncased well bore face. The packer and sand screens are run in place while water is pumped under high pressure through a float shoe to wash the uncased bore and remove drill cuttings and clean well completion apparatus prior to placing the well into production. It is desirable that the wash job be performed as the completion apparatus is run into the well. After the annulus along the uncased well bore has been cleaned, the packer is customarily set to seal off the annulus in the zone where production fluids flow into the production tubing. Inflatable packers are preferred for use in sealing an uncased well bore.